Optical guide, process cartridge, and electrophotographic image forming apparatus

A process cartridge detachably mountable on a main body of an electrophotographic image forming apparatus, said process cartridge comprising:

• (a) an electrophotographic photosensitive member;
• (b) a developing member to be used for developing an electrostatic latent image formed on said electrophotographic photosensitive member;
• (c) a developer containing portion for containing developer to be used for developing the electrostatic latent image by said developing member;
• (d) a first optical guide formed into one united body with a light-transmissive material, said first optical guide including:
• a blocking portion for blocking a first opening formed in said developer containing portion;
• an optical guide portion for guiding light emitted by a light-emitting member provided in the main body of the apparatus into said developer containing portion, said optical guide portion being formed on a side positioned on an outside of said developer containing portion with respect to said blocking portion;
• an outside inclining surface portion inclining toward the side, on which said optical guide portion is formed, with respect to said-blocking portion, said outside inclining surface portion being formed at an end portion of said optical guide portion on a blocking portion side in a lengthwise direction of said optical guide portion;
• and
• an inside inclining surface portion inclining toward a direction intersecting the lengthwise direction of said optical guide portion, said inside inclining surface portion being formed on a side to be positioned on an inside of said developer containing portion with respect to said blocking portion;
• and
• (e) a second optical guide formed into one united body with a light-transmissive material, said second optical guide including:
• a blocking portion for blocking a second opening formed in said developer containing portion;
• an optical guide portion for guiding light that has passed through said developer containing portion to a light-receiving member provided on the main body of the apparatus, said optical guide portion being formed on a side positioned on the outside of said developer containing portion with respect to said blocking portion of said second optical guide;
• an outside inclining surface portion inclining toward the side, on which said optical guide portion of said second optical guide is formed, with respect to said blocking portion of said second optical guide, said outside inclining surface portion being formed at an end portion of said optical guide portion of said second optical guide on a blocking portion side of said second optical guide in a lengthwise direction of said optical guide portion of said second optical guide;
• and
• an inside inclining surface portion inclining toward a direction intersecting the lengthwise direction of said optical guide portion of said second optical guide, said inside inclining surface portion being formed on a side to be positioned on the inside of said developer containing portion with respect to said blocking portion of said second optical guide.

An electrophotographic image forming apparatus to which a process cartridge is detachably mountable for forming an image on a recording medium, said apparatus comprising:

• (a) a light-emitting member for emitting light;
• (b) a light-receiving member for receiving the light;
• (c) mounting means for mounting the process cartridge detachably, the process cartridge comprising:
• (1) an electrophotographic photosensitive member;
• (2) a developing member to be used for developing an electrostatic latent image formed on the electrophotographic photosensitive member;
• (3) a developer containing portion for containing developer to be used for developing the electrostatic latent image by the developing member;
• (4) a first optical guide formed into one united body with a light-transmissive material, said first optical guide including:
• a blocking portion for blocking a first opening formed in the developer containing portion;
• an optical guide portion for guiding the light emitted by said light-emitting member provided in the main body of said apparatus into the developer containing portion, the optical guide portion being formed on a side positioned on an outside of the developer containing portion with respect to the blocking portion;
• an outside inclining surface portion inclining toward the side, on which the optical guide portion is formed, with respect to the blocking portion, the outside inclining surface portion being formed at an end portion of the optical guide portion on a blocking portion side in a lengthwise direction of the optical guide portion;
• and
• an inside inclining surface portion inclining toward a direction intersecting the lengthwise direction of the optical guide portion, the inside inclining surface portion being formed on a side to be positioned on an inside of the developer containing portion with respect to the blocking portion;
• and
• (5) a second optical guide formed into one united body with a light-transmissive material, said second optical guide including:
• a blocking portion for blocking a second opening formed in the developer containing portion;
• an optical guide portion for guiding the light that has passed through the developer containing portion to said light-receiving member provided on the main body of said apparatus, the optical guide portion being formed on a side positioned on the outside of the developer containing portion with respect to the blocking portion of the second optical guide;
• an outside inclining surface portion inclining toward the side, on which the optical guide portion of the second optical guide is formed, with respect to the blocking portion of the second optical guide, the outside inclining surface portion being formed at an end portion of the optical guide portion of the second optical guide on a blocking portion side in a lengthwise direction of the optical guide portion of the second optical guide;
• and
• an inside inclining surface portion inclining toward a direction intersecting the lengthwise direction of the optical guide portion of the second optical guide, the inside inclining surface portion being formed on a side to be positioned on the inside of the developer containing portion with respect to the blocking portion of the second optical guide.